Effect of the Graphitic Carbon Nitride Synthesis Atmosphere on its Activity in the Photocatalytic Generation of Hydrogen Peroxide

Materials based on graphitic carbon nitride (g-C3N4) are intensely studied as promising photocatalysts of different reactions, hydrogen peroxide formation including. Effect of synthesis parameters of g-C3N4 obtained by thermolysis of melamine, urea, and thiourea on its composition and photocatalytic activity has been studied. The photocatalytic activity of obtained materials has been studied in the reaction of oxidative decomposition of organic dye and in oxygen reduction to form hydrogen peroxide. It has been shown that, in spite of incomplete polycondensation after thermolysis, the obtained samples display high values of photocatalytic activity. The work has shown that the photocatalytic activity of samples obtained at 550°С is by factor 2–4 higher than that for samples obtained at 500 and 600°C. It has been shown that the preparation of g-C3N4 from thiourea in air leads to photocatalyst with maximal activity, whereas melamine and urea produce the best catalyst under nitrogen atmosphere.